Sunday, March 11, 2012

The Amateur Crafter: Project 1 – Forced Patina

Well while I’m waiting for some of my equipment to come in, let’s try a little easy-to-learn project shall we?

Forced patina is the act of producing a “weathered” look on an item, in this case, a blade blank. Now the blank I made on a CNC (computer numerical control) milling center so it’s not how I’m going to produce a custom blade at home. But I will at least give some information about it. It’s a project that the students and I wanted to try out to learn a possible manufacturing process.

Photo A


Photo B

The design is modeled after a Benchmade Mini-Griptillian with a drop point tip. Of course our model isn’t a folding knife, it’s a fixed blade. Now we had to be extremely careful about this particular project because we wanted to make sure that we weren’t violating any state or federal laws by learning this process. The end project will not be a finished blade; we can’t do that. But we can make the profile, heat treat it, and make scales (handles) for them. Even though it’s not technically a finished, useable blade, we decided to keep within the blade restrictions. So the overall length is approx. 6” and the blade itself is less than 3 inches. From photos B & C, one can see the similarities of our blade and the Benchmade 556-PNK.

This particular mini-griptillian was a birthday present to my mother. The handle is a pink color to represent Benchmade’s commitment to donate a portion of the proceeds from the sale of this model to an institution dedicated to the study of breast cancer, of which my mother is a survivor.

Photo C


Now for my attempt at a forced patina. I’ve read articles and books and visited web pages and watched videos. But I know that some of the best experience is just to get out and try it yourself. So, for the “agent” I’m using just plain mustard with a bit of vinegar mixed into it. I mixed the two carefully because I wanted the mustard to have a bit more “bite” with the extra vinegar, but I didn’t want it runny. It needed to be more of a gel for easier working. This helped some but I probably would have done better at the application with something like a Q-tip. I was out at the time so I resorted to an old model paintbrush. From photo D, one can see how it was applied.

Photo D

And I learned that mixing the agent too think will cause it to dry too quickly, making the resulting patina fairly subdued. Now, I actually like that look, but I intended for the patina to be darker than that. The first attempt I simply laid the mixture on the handle section in something resembling a pattern. For the second pattern I used a bit of electrical tape that I cut up for smaller pieces. This was just to allow the chance at applying the agent to all areas that I wanted to have a patina on. The first attempt, the agent was more of a gel and didn’t run much. So for this attempt, I made the mix a bit runny and laid the agent on smoothly and as evenly as I could. The result was about the same as the first attempt, perhaps a bit improved.

Photo E

Photo F

Again, I’m fine with that look but I did want the patina to appear darker. But I suspect that because the blank was made from O-1 steel, that it won’t weather quite as good as say 1095 steel. And from the photos, one can see where the mix started to leech under the areas where the tape didn’t quite stick properly to the blade.

Photo G


Photo H

The result created some little “blobs” at the tips of the tiger stripes. Still, for a first attempt on steel that probably won’t take weathering too well, I think it came out pretty nice. I can’t wait to try it out on some softer steel. I’ve managed to find a seller of 1095 steel already annealed so hopefully I’ll have some additional blanks soon.

No comments:

Post a Comment